SPOILER WARNING: This article contains major spoilers for "Crisis on Infinite Earths, Part 2," the second installment of this year's Arrowverse crossover.
"Crisis on Infinite Earths" has already changed course on a major development from its opening chapter. Oliver Queen sacrificed himself to evacuate Earth-38, but his daughter, Mia Smoak, can't stand by and let her father rest in peace. Once she learns of the resurrection powers of the Lazarus Pit, she goes on a mission to bring her father back to life.
This mission turns out to be successful, in a manner of speaking. All of the Lazarus Pits on Earth-1 were destroyed by Oliver's sister, Thea, which sends Sara, Mia, Flash and John Constantine to another Earth in the multiverse that still has a Lazarus Pit. Though Sara warns Mia of the dangers that come with using the supernatural pits, they go through with tossing Oliver's corpse in it. The Lazarus Pit brings Oliver's body back to life, minus a soul.
Now, they must go on another mission to reunite Oliver's body with its soul, so it doesn't remain a mindless rage monster.
"Crisis on Infinite Earths" continues in The Flash on Tuesday, Dec. 10 at 8 p.m. ET/PT. After the winter hiatus, the crossover will conclude on Tuesday, Jan. 14 in Arrow at 8 p.m. ET/PT and in DC's Legends of Tomorrow at 9 p.m. ET/PT.